It's very hard to place what is so pleasing about this drawing. I don't usually go for such a vibrant, hot colour scheme, but the way it's been used in this piece was very sensitive, and the result is surprisingly still and calm. One definitely has the impression of sunset, and yet it is the figures, and not the sky, which give this impression.
The stonework is actually all the more charming, because it is not strictly foreshortened into a flat plain, but almost looks alive, and yet completely serene.
I suspect that there is a lot of traditional symbolic meaning in the picture, which I don't know much about, but am now intensely curious about. The fact that the central figure, (who I suspect is an itinerant warrior of some sort), is sitting on a shield, and the glyphs engraved on the posts the dragons are sitting on, are all deeply meaningful, or at least give that impression.
This style of drawing reminds me a little of the early gothic prayerbook drawings from the medieval era, which is a style I find very pleasing, but it's somehow so satisfying to see this style used in an ancient Chinese setting.
The expression in the warrior's eyes is very bright, as though he might either be inebriated slightly, he's just recognized the viewer as a friend, or he's just seen an enemy. The enigma is very compelling.
Although the fact that he's sitting on his shield with his hands on his knees, makes me think of a challenge of some kind, the overall mood is something much more profound, which makes the piece all the more interesting.